Mainly written from the perspective of a tourist. They could handle customers who can only really speak English haha!
Remember that Ground 0 means essentially the basement floor. Be aware that you will have to climb down a set of stairs to get to the entrance door. From what I can tell, there's no other way down there. A few months ago, I injured my lumbar a bit, and I can say I would have trouble getting down there without a lot of assistance. Definitely not wheelchair accessible.
BLU BASE Jianbing & Bubble Tea was convenient in that it was the closest when I was walking around the Binnenalster (Inner Alster Lake). It's super anime-themed, with even anime-themed snacks. Selection-wise, the drink menu so far most resembled what I'm used to in the Bay Area. They have more Asian-specific flavors like snacks with pork floss and taro and drinks with yuzu and red bean. Most importantly, it IS one of the boba places that lets you adjust sugar and ice levels and they even do hot drinks. The other thing they advertise is their jianbing, but I didn't try it and there were other cute, somewhat anime-themed snacks.
Be aware that this IS in Hamburg-Altstadt and they are within walking distance of many of the bus stops and major tourist destinations in Altstadt (including Hamburger Rathaus and all the restaurants). I personally love how tucked away they are. They even have a gaming system with Super Smash set up, so it really seems like a spot you can really casually hang out in for a while (something I realize that you can't do at a lot of cafes). They are not the only boba place in the area, but this one is really cute. read more